Received: from malur.postgresql.org ([217.196.149.56]) by arkaria.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vO9RJ-00CJPW-0u for pgsql-hackers@arkaria.postgresql.org; Wed, 26 Nov 2025 06:55:45 +0000 Received: from localhost ([127.0.0.1] helo=malur.postgresql.org) by malur.postgresql.org with esmtp (Exim 4.96) (envelope-from ) id 1vO9RH-00Eglm-2q for pgsql-hackers@arkaria.postgresql.org; Wed, 26 Nov 2025 06:55:44 +0000 Received: from makus.postgresql.org ([2001:4800:3e1:1::229]) by malur.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384 (Exim 4.96) (envelope-from ) id 1vO9RH-00Egld-1n for pgsql-hackers@lists.postgresql.org; Wed, 26 Nov 2025 06:55:43 +0000 Received: from mail-qt1-x844.google.com ([2607:f8b0:4864:20::844]) by makus.postgresql.org with esmtps (TLS1.3) tls TLS_ECDHE_RSA_WITH_AES_128_GCM_SHA256 (Exim 4.96) (envelope-from ) id 1vO9RF-001Wmq-1g for pgsql-hackers@lists.postgresql.org; Wed, 26 Nov 2025 06:55:43 +0000 Received: by mail-qt1-x844.google.com with SMTP id d75a77b69052e-4ed75832448so86658611cf.2 for ; Tue, 25 Nov 2025 22:55:42 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1764140141; x=1764744941; darn=lists.postgresql.org; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:from:to:cc:subject:date :message-id:reply-to; bh=YjsHPuo25Vl8fV9/MhBuwQUetSs/mMFhkv0EoyIuXEo=; b=h7TDQ1ijtKPcGqNvNqp5ay8YZfQI7vp/gXfIty2thGia3578CCszrHJ9uqdOBbOU34 qcAVH1rqHPGA5yJfOydilLFIDkg3BZWkfc9QyYgeO91VTyS3YgH6eoh3pYLwXuRMEe+s X7F2zPd/+dpmMeO+pJv7umkf9/X0Jk+CgquFNOWzQUTjHZVNdh+dJWDEf6h4A7P7k4j3 s2vBxODkSr3bpzfttBmctj2/sypF4HF6p96ZVa+wPiSJTXTRJF7KlhlQ/uIrD2StAWVU vPO3H/NGXUcy2+Nkc2iZcGwF2XkP5eB0avtOBal/iZANuusTewobgVqCPqoUZknoE04Y ursw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1764140141; x=1764744941; h=content-transfer-encoding:cc:to:subject:message-id:date:from :in-reply-to:references:mime-version:x-gm-gg:x-gm-message-state:from :to:cc:subject:date:message-id:reply-to; bh=YjsHPuo25Vl8fV9/MhBuwQUetSs/mMFhkv0EoyIuXEo=; b=fv2KwySPAUq9t0J+kIzCPoZcacOgbtZW2fs2/P2+V8WS4a76/a8ozi2ZFr9WCqys7e GZuFLO2Uy3WQGNTSlVlphf4xxpC7Sy87gI+MLfu4fNxibteEh8kgfGPkLaZMX8Wg4v+K U2ZmJp1gBwHQpwSAmDTqKFTu+R0mJYBQB8ba/lRcg40DawBnOBybRStbZ+iHGdjgual7 sZ2e0VYNbQ5i/lm60a+fD5sccP9+Emu4603ItzkaHzy2ub+nmJnBltYpDJQZCux7QbAh BSbnveVkT2OWymoYCuoRGFn42o2ORQr1ugtRIZpP5LkAHHa9ubCtMufTQ64MMTfi730L IxvA== X-Gm-Message-State: AOJu0Yzdc4gHccyQG3/3VKQ9iIsiwwoZqhkfrqFr9WSJLRt6njHE00j4 7MVrwO2FjpPZ5NSChOjzfm3LSQWO/w8sZs80iJ+abd5PZr1SJNvns4xmnRFjA6W305Xs9bEt08c 1qKEnd4NivZaJ9BxvRRhcctEjoxgoxcYZ091m X-Gm-Gg: ASbGncvBn4Q3FjLXmckYIMj19mYDW7f12iYkRrLX1s1nLZyhBlyEMZWXWPchjCoRdzP u/tQDuCWUGAjApwEo6B/kYUh3oGk7jQbKqjTwrAOkA19e2k9IQRIZp0schuvvB+RTH6veHPJIPk 3IN4Amu2fAh4vouQepf2A75n9UZealseZ3MayGoUskYHL4VIffWoh5Q0UXNpoIUFpysrPlMII34 YAJnsIVlfuW1PbPIRpbHzM79OToSZFRGfBWRl/f0s3oSs/AEZvjrhmFRIPYyDuWXI9xzg63e8v6 8E4vVDID3rGlBlwfh1296gBr4VWKS0IyB8fw/Fgal2ZnxpgpAw1JIIB7M2zq0qADOpe2Rg0xF8k Qt3rzLH84t3E2/iA= X-Google-Smtp-Source: AGHT+IEEH5dEcUYWoc2HFAwejDv9NXt6H4r1rsDZzlOfNKRsTZIaqU9oD112XkpYXZlEifPVkCisAZ5+FahKr7qOcHg= X-Received: by 2002:a05:622a:1308:b0:4ee:26bd:13f3 with SMTP id d75a77b69052e-4ee58a61bf6mr218948181cf.8.1764140141587; Tue, 25 Nov 2025 22:55:41 -0800 (PST) MIME-Version: 1.0 References: <269A8FB9-6D43-43CF-A6FE-52D28CBDB8A9@Outlook.com> In-Reply-To: From: John Naylor Date: Wed, 26 Nov 2025 13:55:30 +0700 X-Gm-Features: AWmQ_blEKm8G1gRtLlgBoVQ6WlrCymixvERWuEigS8LXSeUO5SfeEc9I9anyNKk Message-ID: Subject: Re: tuple radix sort To: Chengpeng Yan Cc: "pgsql-hackers@lists.postgresql.org" , Peter Geoghegan Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable List-Id: List-Help: List-Subscribe: List-Post: List-Owner: List-Archive: Archived-At: Precedence: bulk On Wed, Nov 26, 2025 at 1:52=E2=80=AFPM John Naylor wrote: > This made me think of something tangential: v4's common prefix > skipping doesn't take into account that the upper 4 bytes can't > matter. With a mix of positive and negative integers, I think it will > do the radix sort on all 8 bytes of "datum1". I accidentally edited out some context: The above is referring to SQL "int" sort keys, i.e. 32-bit signed integers. --=20 John Naylor Amazon Web Services